Fewer and fewer people are prepared to pull on the black shirt of officialdom as high-profile incidents of referee-haranguing set harmful precedents for the next generation of footballers.

Neil Connor explores some of the major confrontations...

Most footballers wear the bling bling jewellery, but who would have thought that other more unsavoury elements of gangster rap are finding there way into the sport as it becomes flooded with cash and ultra-celebrity.

There's easily more swearing at a high-profile Premiership game than at an Eminem concert these days, with most of it directed towards the referee.

But with world class officials such as Anders Frisk having to retire because he has become the target of death threats, things have really gone to far.

Referees have long been the focal point for footballers who need someone to take out their frustrations on.

Paolo Di Canio, never one to be far away from controversy, was perhaps the first of many recent culprits for his now famous act of aggression carried out when he played for Sheffield Wednesday in a match against Arsenal.

After getting himself involved with a free for all with Martin Keown and Patrick Vieira, Di Canio was shown the red card and promptly responded by pushing referee Paul Allcock to the ground.

The incident earned the fiery Italian an 11-match ban, but this did not deter other highly-paid premiership stars from targeting officials.

Two years later, in 2000, Roy Keane was under the spotlight for all the wrong reasons.

The Manchester United caption led a group of players who chased the referee into a corner at Old Trafford. The referee's crime? He had the nerve to award a penalty against United at their own ground.

A more recent United starlet, Wayne Rooney, is starting to gain an unsavoury reputation for abusing referees.

At Crystal Palace recently he was booked for persistent swearing. This follows him having to be restrained by team mate Gary Neville at the game against Arsenal in February after continuously insulting the referee.

Frisk's retirement in the wake of death threats after a European Champions League game against Chelsea led to UEFA's refereeing chief Volker Roth accusing the Blues' manager Jose Mourinho of being "an enemy of football".

Scandals which thankfully do not involve players have also been engulfing referees across Europe.

Two referees in Germany have been arrested by police looking into match-fixing activities. This has led to talk of a referees' strike and reports in newspapers that referees had become more error-prone since the arrests.

In the Czech Republic, some 14 referees, seven club officials and four representatives of the national football federation have been punished for their part in a bribery scam.

It is no wonder that Britain is losing referees at a faster rate than they are being created.

They are abused on the pitch, from the terraces and now by anonymous people on the end of telephone lines, but like them or loathe them, referees are as important to the game as the millionaire footballers who they share the field with.